Save the running world before importing a world file (t79)

docs/agent-log.md

@@ -4,6 +4,16 @@ What agents have done, newest first. Add an entry for every piece of work: the d
 note or request it was for, what changed, the files touched, the tests run, and anything left
 open or not verified. Keep each entry short; the git history has the details.
 
+## 2026-10-29: t79 preserve progress before world import (Codex)
+
+- importWorldFile uses GAME.running to await saveWorld('auto', true) before reading
+  the file or starting loading. Save failure cancels import with a toast.
+- Files: src/ui/saves.js, test/t_import_save.js, tasks/t79_importing_world_mid.md
+  and this log. Regression failed first; seven focused checks, build.py and all
+  headless suites passed (python3 test/run_all.py; /tmp/t79-headless.log).
+- Browser suite and screenshots not run as requested; owner playtesting remains
+  open. No simulation/worldgen changes; no commit.
+
 ## 2026-10-29: t78 damaged blueprint code validation (Codex)
 
 - bpValid checks block codes, non-fixed machine types and mold kinds against their